Microsoft Defender February 2026: AI-Powered Security, Unified Portal, and Enhanced Identity Protection

Microsoft continues to evolve its security portfolio with significant updates across the Defender suite in February 2026. The monthly roundup highlights AI-driven incident management, deeper integration between Microsoft Sentinel and Defender, and expanded identity protection capabilities that reflect the industry's shift toward unified security operations.

AI-Powered Incident Prioritization Transforms SOC Operations

The most significant announcement is the public preview of AI-powered incident prioritization for Microsoft Defender. This capability directly addresses one of the most pressing challenges in security operations centers: alert fatigue and the inability to distinguish critical threats from noise.

SOC teams traditionally spend countless hours triaging alerts, many of which turn out to be false positives or low-severity events. Microsoft's new built-in alert tuning rules automatically reclassify certain alerts as behaviors, removing them from the open alerts queue while keeping them available for investigation when needed. This intelligent filtering ensures analysts focus on high-quality, actionable incidents that represent real threats.

The technology leverages machine learning to understand patterns and context, automatically handling informational and low-severity alerts in the background. This represents a fundamental shift from reactive alert management to proactive threat prioritization, allowing security teams to respond faster and with greater confidence.

Microsoft Sentinel's Complete Migration to Defender Portal

A major strategic move is the retirement of Microsoft Sentinel in the Azure portal, scheduled for March 31, 2027. Microsoft Sentinel is now generally available in the Microsoft Defender portal, even for customers without Microsoft Defender XDR or an E5 license. This unification creates a single pane of glass for security operations, eliminating the need to switch between multiple portals.

The migration includes comprehensive resources, including a two-part webinar series that walks through a day in the life of a SOC, demonstrating how integration and simplicity make security operations smoother in the unified portal. The first part focuses on onboarding and getting Sentinel Defender-ready, while the second covers completing the migration.

This move aligns with Microsoft's broader vision of XDR (Extended Detection and Response), where security data and workflows converge into a cohesive experience. Organizations can now leverage Sentinel's powerful SIEM capabilities alongside Defender's endpoint, identity, and cloud protection within a single interface.

Enhanced UEBA Capabilities with Behavioral Insights

Microsoft Sentinel introduces a UEBA behaviors layer that transforms high-volume, low-level security logs into clear, human-readable behavioral insights. This AI-powered capability aggregates and sequences raw events from supported data sources into normalized behaviors that explain "who did what to whom" with MITRE ATT&CK context.

The system now allows enabling UEBA for supported data sources directly from the data connector configuration page, reducing management time and preventing coverage gaps. The Triage MCP (Model Context Protocol) server provides access to APIs for incident and alert triage, enabling autonomous investigation workflows or custom agentic solutions built on top of Defender and Sentinel alerts.

These enhancements represent a maturation of UEBA from simple anomaly detection to contextual behavioral analysis that security analysts can immediately understand and act upon.

Identity Protection Reaches New Levels of Sophistication

Microsoft Defender now supports Entra Agent IDs, extending comprehensive security capabilities to agent identities. Previously, agents used User OBO (User on Behalf Of), but now organizations can specify dedicated identities for their agents. This granular control enables better governance, discovery, and protection of automated workloads and service accounts.

The BehaviorInfo and BehaviorEntities tables in advanced hunting now include additional columns and information about behavior data types and alerts from User and Entity Behavior Analytics (UEBA), providing deeper insights into the relationships between identified behaviors and entities.

Microsoft Defender for Identity receives significant enhancements with the general availability of identity inventory improvements. The new Accounts tab provides a consolidated view of all accounts associated with an identity, including those from Active Directory, Microsoft Entra ID, and supported non-Microsoft identity providers. Security teams can now manually link and unlink accounts, perform identity-level remediation actions like disabling accounts or resetting passwords, and leverage the new IdentityAccountInfo table in advanced hunting.

Office 365 and Cloud Apps Security Updates

Microsoft Defender for Office 365 introduces automated threat protection capabilities for Microsoft Teams. Admins can now directly block malicious domains and email addresses from within the Defender portal, seamlessly adding targeted entries to the Teams Admin Center blocked domains and users list. This near real-time protection halts new external chat messages, invites, and channel communications from blocked domains while deleting existing ones.

The expansion of Zero-hour-auto-purge (ZAP) and Teams admin quarantine to Plan 1 brings post-delivery protection to more customers. These capabilities automatically remove malicious content from user mailboxes after delivery, providing an additional layer of defense against phishing and malware.

Defender for Cloud Apps simplifies security with the Workday connector now requiring only "View" permissions instead of "Modify," better aligning with the principle of least privilege. Existing configurations continue to work, but administrators are encouraged to update settings as a security best practice.

Vulnerability Management and Secure Score Enhancements

Microsoft Defender Vulnerability Management introduces two critical Secure Score recommendations: disabling the Remote Registry service on Windows and disabling NTLM authentication for Windows workstations. These recommendations address significant attack vectors - the Remote Registry service prevents unauthorized configuration changes and lateral movement, while disabling NTLM mitigates credential theft and Pass-the-Hash attacks.

The Vulnerable devices report experience is streamlined with simplified filters, a 30-day history limit, and removal of the Windows version breakdown section. These changes focus attention on current, actionable vulnerability data rather than historical trends.

SAP and Multi-Tenant Management Improvements

Defender for Cloud Apps expands SAP BTP detection coverage, strengthening visibility into high-risk control plane, integration, and identity activities. This enhancement is crucial as organizations increasingly rely on cloud-based ERP systems that present unique security challenges.

Multi-tenant management now supports content distribution for Analytics Rules, Automation Rules, and Workbooks, allowing customers to quickly onboard new tenants and maintain consistent security baselines across their organization. This capability is essential for managed security service providers and large enterprises with complex tenant architectures.

Technical Improvements and User Experience

The update includes practical improvements like partial query results in advanced hunting when results exceed the 64-MB size limit, preventing data loss while informing users about truncated results. The enhanced RPC auditing requirement for some Defender for Identity advanced identity detections includes new health alerts to identify sensors with missing or incorrect configurations.

Automatic Windows event-auditing configuration for sensors v3.x is gradually rolling out, streamlining deployment by automatically applying required auditing settings to new sensors and correcting misconfigurations on existing ones.

Strategic Implications for Security Operations

These updates reflect Microsoft's strategic vision for security operations: unified platforms, AI-driven automation, and comprehensive identity protection. The migration of Sentinel to the Defender portal eliminates portal fragmentation, while AI-powered incident prioritization addresses the fundamental challenge of alert fatigue.

The enhanced identity protection capabilities acknowledge that modern attacks increasingly target service accounts, agents, and machine identities rather than just human users. By extending Entra Agent IDs and improving identity inventory management, Microsoft provides the tools needed to secure the entire identity landscape.

For organizations evaluating their security strategy, these updates present compelling reasons to consolidate on the Microsoft security ecosystem. The unified portal experience, combined with AI-driven automation and comprehensive coverage across endpoints, identities, cloud apps, and email, creates a powerful integrated defense.

However, the transition also requires careful planning. Organizations using Sentinel in the Azure portal must begin migration preparations, and those leveraging multi-tenant management need to understand the new content distribution capabilities to maintain consistent security postures.

The February 2026 Defender updates represent more than incremental improvements - they signal a maturation of Microsoft's security vision toward truly integrated, intelligent, and identity-aware protection that addresses the evolving threat landscape.